| Summary | Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to validate the response body of proxied images, which allows a remote attacker to enact client-side DoS via an SVG file served from an attacker-controlled origin under a non-SVG Content-Type header (e.g. image/png) embedded in an og:image meta tag or Markdown image link.. Mattermost Advisory ID: MMSA-2026-00630 |
|---|---|
| Publication Date | May 16, 2026, 4:17 a.m. |
| Registration Date | May 17, 2026, 4:13 a.m. |
| Last Update | May 16, 2026, 4:17 a.m. |
| CVSS3.1 : MEDIUM | |
| スコア | 4.3 |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
| 攻撃元区分(AV) | ネットワーク |
| 攻撃条件の複雑さ(AC) | 低 |
| 攻撃に必要な特権レベル(PR) | 不要 |
| 利用者の関与(UI) | 要 |
| 影響の想定範囲(S) | 変更なし |
| 機密性への影響(C) | なし |
| 完全性への影響(I) | なし |
| 可用性への影響(A) | 低 |